Arithmetic-teaching device



'March 31. 1925.

1,532,011 R; M. WILLlAMSON fr..

- ARITHMETIC TEACHING DEVICE Filed Ma rch 21, V17924 l I I l Patented Mar. 31, 1925.

UNITED S'I'ATIES` ROBERT MARSHALL WlLLIAlVLSON, OF BUBLEY, BROCKENHURST; ENGLAND.'

ARITHMETIGTEACHNG DEVICE.

Application filed March 21, 1924. Serial No. 700,839.

To all whom 'it may concer/n:

Be it known that I, ROBERT MARSHALL lVILLrAMsoN, a subject of the King of Great Britain and Ireland, residing at Burley, near Brockenhurst, in the county of Southampton, England, have invented an Improved Arithmetic-Teaching Device, of which the following is a specification.

This invention relates to devices of the kind in which tablets or the like are movable along guides and it has for its object to provide an improved ap Jaratus adapted to teach visually the decimal system of ciphering whether of whole numbers or of fractions. To this end the apparatus is characterized by a base which is stepped upwardly inl a direction from right to left, with each of which steps is associated a guide and plurality of distinctive indicating tablets movable therealong, the whole being such that "a series of columns of tablets are presented to a learner in the same way as columns of figures appear. The advantage of such an apparatus resides in the facility Lil) with which one can impress upon the learner the importance of position as affecting` values so that the common mistake of failing to keep figures in appropriate columns is avoided. The gradation of the base in,V

steps may be emphasized by a color gradationin addition.

A further feature of the invention consists in the employment of frames each adapted to slide in relation to the column of tablets and capable of temporarily embracing a limited number thereof, not however exceeding nine, which is the largest single number, so that itis necessary 1ndemonstrating addition, for example, to show that after nine tablets have been established in one frame the adding of another involves the inclusion of a single tabletin thel frame of a column next higher in order, ouin other words the exchangeof a tablet .marked l0, for 10 tablets marked 1 and so on, it being understood that the tablets in each individual column are marked alike.

These and other features will appear from the constructional example now about to be described with the aid of the accompanying drawings, whereof Fig. 1 is a plan and Fig. 2 a transverse section on the line 2-2 Fig. l. Figs. 3 and 4c are sectional views illustrating two detail modifications.

As shown in Figsl and 2 the base of the device consists of a rectangular box-like board a the upper surface of which 1s graded -inlevel as a regular series of steps l), of any number, but preferably not less than three.

For convenience in storing the board, which may be advantageously though not necessarily made'in one piece, the aforesaid steps bare made so that the tread or surface of'each is vbrought into a horizontal plane when the left side of the board is raised suiiiciently; and the board is to be used when secured as a whole in that inclined plane, the highest step'being at the left-handl side, and the lowest step at the right-hand side, of the board.

The upper surface of the board is also preferably colored in a gradation of tints or depth of one color, it may be grey, the depth of color increasing with the fall in level of the steps, but each step, save as hereinafter provided, being colored uniformly.

Thel steps are conveniently though not necessarily made singly of ply-wood or other suitable material, and may extend between two members 0 separated by a slight space Z from the ends e.

Three wires f, g. and 7i or parts of a single wire laced to and fro between the members c which thus act as straining-plates, run along and above each step, the wires, f and g being to the left and the wire h to the right, of the central line of the step. The left-hand wire, f may be placed at a slightly greater height above Ythe step than the wires g and z. J

Each step is provided with numerous, preferably not less than twenty-seven, fiat J narrow tablets i of aluminium or other material and of uniform shape and size, the length of each, it may be, about one half of the width of the step. The ends of the said tablets are formed` as rings or otherwise adapted for easy passage along the wires Ir] andv li preferably without touching the steps.

Alternatively the wires and 71. may be replaced by rails, such as by a member constituting rails 'y' as shown diagrammatically in section in Fig. 3 or rails jl as in Fig. et., the said members resting on the steps, ,and the ends of each of the aforesaid tablets being formed correspondingly to fit loosely within the said rails, as shown sectionally at l and ci? in Figs. 3 and 4.

All the tablets z' are preferably colored on their upper surfaces, all on each step being colored uniformly, but the tablets on no two steps being colored alike, this feature, like the gradation of level and possible grada- `tions lof coloration of the surface o-f the board, being designed to emphasize the positional values of the said tablets. Each tablet also preferably bears a number, in white or other distinctive color, on its colcred surface, the tablets on each step being numbered alike and the number `on each tablet on Vany one step `being one tenth of the number on each tablet on the next step, if any, `to the left, and'ten times the number on each ftablet on the `next step, if any, to the right of the same, according to the decimal systein-of ciphering. If the board be not designed to afford object lessons in decimal fractions each tablet v'on the lowest or `eXtreme right-hand step lwould be numbered l, and each tablet on successvie steps to the left thereof l0, l0() serially as shown `in Fig, l. If 'the board be designed to afford object lessons `in deci-mal fractions as well as whole numbers ythe tablets preferably on thecentra'l step, or `on the step linnnediately to ithe `left of the central line ofthe board, -would each 'be numbered l, and Ithe tablets on steps `to left and right of lthe said step would each be numfbered l0, and 1., Ol i respectively and serially. In this latter ease 'the step bearing tablets numbered l is made wider than the normal step, a strip along Ithe right-:hand side of .its surface, corresponding to its extra width, is distinctively and conspicuously colored, it may :be in white, and Ymarks are formed thereon prominently, it anay Ibe `in black, at moderate intervals, failong fthe entire length lof vthe `said strip to represent Ydecimal .ipo-ints.

Each lstep is further provided with not less than :two smalrlopen rectangular fran'ies 71:, of aluminum or other material, 'all of uniform shape iand size, the left-hand edge .of each frame being formed to fallow of its easy passage -along the wire, supported partly yby such wire and partly by the operators rhfand or by the wire -z` vat its yright hand side. The frame Z: is adapted to lbe revolved Vabout the left-hand wire In leach frame a rectangular opening fm, is cut adapted Vto lespose the colored -and nun'ibered sur-faces of nine tablets and short 4|flanges la are provided :at the ends of; the opening adapted to venclose between them nine tablets, but ynot more than nine, and to prevent the independent passage of the tablets along the wires when the frame e11- closes them. Each 4frame when not being supported independently by 'the operator may rest either horizontally `on the wires g yand 7L, or in a plane suitably inclined to the vertical, supported by wire and by the edge either ofthe next step 7) vto the left or of the side of the box board as the case may be.

Small holes are made in each step o, between wires g and h, at intervals slightly greater than :the length of the frames 7c, and small pegs 0 of wood or other inaterial are .provided adapted to be inserted therein and obstruct passage of the said frames or tablets .along the steps. If the board be made in one piece a light top may be provided to slide in a groove p in opposite sides.

Two legs 7 are provided each movable hingewise and adapted at one time to support 'the board in inclined position when in use and at another time to be housed in the yspace d in the board, for example. When the board 4is in use each leg is secured in vertical position as by a wire strut r, engafging rings s, lixed in the lleg and in the end Aof the board.

TWhat I claim is l. lIn a device of the kind described, a base the surface rof which is provided with a Irange of steps, a plurality of indicating tablets associated with each step, guide means whereby the tablets associated with any one step can be slid columnwise in relation te each step, fand means whereby movement `of Itablets separated from others in afcoluninfcan belobstr'ucted.

i2. In a device of lthe ikind described, a ibase, a plurality fof indicating tablets, guide means whereby the tablets can be slidably supported `in columns, and slida'ble means :adapted to be temporarily lengaged with and thus select, :isolate vand collectively move certain 'of the tablets ina column.

In a device 'of the kind described, a base, a plurality of indicating tablets, guide means whereby the tablets ycan be slidably supported in columns, slidable means adapted to be temporarily engaged with and tlrus select, isolate and collectively move certain of fthe tablets ina column, fand means for obstructing movement of the ylast mentioned means when so desired.

4. 'In a device of the kind described, a base 'the surface of which is provided with a range of steps, fa 'plurality iof indicating tablets Aass f ciafted with each step, guide means whereby the ztablcts associated with any one ste-p can rbc slid columnwisc inv relation to such step, and slidablc means adapted :to be tenniorarily engaged with and :thus select, isolate and collectively move certain of the tablets in a column.

5. In a device of the kind described, a base, lthe surface of which is provided with a range of steps, a lplurality of indicating tablets associated with each step, guide means whereby the tablets associated with any one step can be slid columnwise in relation to such step, slidable means adapted to be temporarily engaged withfand thus selec@ isolate and collectively 1nove ce1'- teblets adapted to slide along two of the tain of the tablets in a column, and means guides and a frame adapted to slide or for obstructing movement of the last men- J0 be allgulally ttned about the third 10 iioned means when S0 desired, guide, substantially as described.

5 6. In a device of the kind described, e Signed at SOUthamptOH, England, this buse provided With a range of steps, three WeHty-@ghth day 0f February, 1924:. sets of guides associated with each step, `ROBERT MARSHALL WILLIAMSON, 

